1. Field of the Invention
The present invention relates to a tool spindle device such as a grinding wheel spindle device wherein an antifriction bearing rotatably supporting a tool spindle such as a grinding wheel spindle is lubricated with oil air or oil mist.
2. Discussion of the Related Art
In a wheel head wherein a grinding wheel spindle is rotatably supported by antifriction bearings such as roller bearings, ball bearings or the like, the antifriction bearings are lubricated with oil air. In a grinding wheel spindle device of this kind, oil air is exhausted to the atmosphere after being used to lubricate the antifriction bearings, as described in Japanese unexamined published patent application No. 9-11108 for example.
In the grinding wheel spindle device described in the Japanese patent application, since oil air is released to the atmosphere, an adverse effect is likely to be brought about on the surrounding environment, and oil is uneconomically consumed without effective use.